There are some people that already have the mod and clutch fans keep coming on, they added an engine oil cooler and it seems to work..talk to Brian about it, I think he has the killerbee setup and there's a DIY on the DD about them, I will be buying one soon, keeps oil pressure from dropping as well..

Air intake mods will have little effect on coolant temps. I know because I tried them as well as all the other "guaranteed" fixes. The only things I did not try was the oil cooler and methanol injection. At the time the best results were with a system designed by a guy named Chris that incorporate d an auxilary radiator. Unfortunately his kit was no longer available so I was left to design my own.

I designed a system using an auxiliary radiator and for the next 3 years helped over 60 people install this system for free in their trucks with very good results. Of the 60 trucks about 5 still got warm under stress but were night and day difference over stock. Since then I have used feedback to make this system better and better. For the most part we had resolved the issue.

As for oil cooling I've heard mixed. Some trucks (once coolant temps are in check) expeience no excessive oil temps, some do see excessive oil temps. Some trucks with oil coolers claim to no longer have coolant temp issues some still do see excessive coolant temps. One truck in particular continued to experiece excessive oil and coolant temps after trying both an aux cooler and an oil cooler (at different times).

With that said I can confidently advise you that if you have excessive coolant temps, you need to first make sure your factory cooling system is functioning properly, then add cooling capacity with an aux cooler. If you have excessive oil temps you need to make sure your getting proper oil flow then look into oil cooling. If you are experiencing excessive oil and coolant temps you need to do all of the above.

Turbo mouthpiece, cold air intake, cat removal, egr delete, pcv rerout, programming etc will make your truck run better and drop egt's but their overall effect on oil and coolant temps will be minimal compared to the effect of direct cooling.

To further prove my point, look at how GM resolved the issue with the lbz. They increased cooling capacity by 30 percent and created a fan and shroud setup capable of overcoming the air flow issues inherent in the trucks design. They also incrrased the size of the Trans cooler, added another gear (which lowered engine rpm), increased horsepower which allowed for the use of taller gears and decreased compression ratio to lower combustion temps. None of these incorperate the so called "guaranteed" fixes yet they worked well at keeping temps in check.

Now the lbz will still get hot if you push it hard enough by any forced induction diesel will. You just have to figure out how to compensate for it should you truck not be able to perform to your expectations/ application.

Just my 2 cents

Joe

P.s. Sorry for any typos this was done from my phone, computer is in the shop.

At the time the original article was written, the 'cause' of load induced LLY overheating was fairly well understood by us, and just becoming public in papers we decided to make public to bring an understanding of the problem. Then people could decide if they wanted to bandaid the issue by trying to arrange for additional cooling, or eliminate the source of the extra heat. Obviously we went for the latter.

Except perhaps GM, nobody had more time logging it than we did. For his project, we gave Joel some important known information, and suggested logging specific parameters as he went on to his own proving ground methods. We were in contact via email during this time, and he was tickled at what he found, and we were not surprised at his results. We had already seen them. You can view more technical articles about "thermal feedback", if that is your thing, on the induction section of our site.

Lastly, I will add, on ANY stock LLY, it is not possible to overheat the engine coolant without first overheating the oil. Anyone claiming to have normal oil temperatures is simply not working the truck.

At the time the original article was written, the 'cause' of load induced LLY overheating was fairly well understood by us, and just becoming public in papers we decided to make public to bring an understanding of the problem. Then people could decide if they wanted to bandaid the issue by trying to arrange for additional cooling, or eliminate the source of the extra heat. Obviously we went for the latter.

Except perhaps GM, nobody had more time logging it than we did. For his project, we gave Joel some important known information, and suggested logging specific parameters as he went on to his own proving ground methods. We were in contact via email during this time, and he was tickled at what he found, and we were not surprised at his results. We had already seen them. You can view more technical articles about "thermal feedback", if that is your thing, on the induction section of our site.

Lastly, I will add, on ANY stock LLY, it is not possible to overheat the engine coolant without first overheating the oil. Anyone claiming to have normal oil temperatures is simply not working the truck.

You are incorrect sir. Thermal feedback is BS, it has been proven by countless people who have tried to fix it with all the cold air intakes and other "proven fixes" with little to no benefit. The reason we have resorted to your so called "bandaid fixes" is because they are the only fixes that work.

And yes it is possible to overheat coolant without overheating coolant. Oil and coolant temps do not always increase parallel to one another. Engine rpm, egt, engine load etc all effect oil and coolant differently. This has been witnessed in multiple trucks that Were towing across the desert at max gvw in the dead of summer.

You can provide all the "data" and "statistics" you want but in the end the true results are still the deciding factor and all you have to do is ask those that have already been down that road and have no alternative reason to say anything other that the truth.

The fact it that article is old and in the latest maxxtorque article recarding lly overheating they themselves stated the onle proven fix to overheating in the lly is a secondary cooling system of some type.

Go ahead and attack with your walls of text and all your "data". You will convince some you are right, and you will sell them some parts. Then when they are still overheating they will at least know how to actually fix their truck.

Funny how this oil cooler vs aux rad arguement still comes up from time to time.......ironically both are doing the same thing (ie adding additional cooling to the engine but the effects are subtly different). Long story short, best way to eliminate it is to address turbo airflow (LBZ mouthpiece), block your EGR (prevents loss of boost pressure), larger trans cooler (removes more of the heat load), larger aux cooler (adding additional cooling capacity is key to the overall fix) and tuning with EFI (again helps with EGTs under load).

I did not intend for this to an aux cooler vs oil cooler discussion. Both have had positive results. I am currently working on a project that will address both. The other mods like tranny coolers, cai's, turbo MP's, tuning, deleted cats etc will improve longevity, driveability and may help coolant temps and oil temps some but they have nowhere near the effect that direct cooling on either fliud.

You are correct Mtl in that oil and coolant temps are not the only issues to be addressed. They are just the most in your face issues at first.

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